


Merely Imaginary

by Neriede



Category: Kingdom Hearts
Genre: Gen, Sorikai - Freeform
Language: English
Status: Completed
Published: 2014-03-25
Updated: 2014-03-25
Packaged: 2018-01-16 23:40:59
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,521
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/1366012
Author URL: https://archiveofourown.org/users/Neriede/pseuds/Neriede
Summary: <blockquote class="userstuff">
              <p>Math never was Sora's strong suit. Neither was homework in general, but that's besides the point.</p>
            </blockquote>





	Merely Imaginary

**Author's Note:**

> Let’s pretend I don’t have writer’s block for my other projects. Let’s also pretend that this is going to help unblock it.

When he came back, they called him a hero for the things he'd faced, the things he'd seen.

Sora had countless hours under his belt flying the gummi ship, with nothing but the blank emptiness of space to entertain him.

He had seen the blankness of Kairi’s life-less eyes, the eyes of a doll, so porcelain and vacant, and found nothing but courage and determination in himself.

He had stared into the blank recesses of the darkness and not flinched an inch.

He had forgotten how powerless a piece of paper could make him feel.

Pencil poised above eleven by eight inches of clean whiteness, and Sora couldn’t even think of how to begin. He was vaguely aware that he was supposed to transfer his thought process onto the paper, but as is often the case with young boys attempting to do their homework, the intimidating blankness of the empty page seemed to fill his vision, engulfed it until it consumed his thoughts, until his thoughts matched the paper, and his mind drew a blank.

So much white, bound inside the straight edges of a definite shape, and yet it still seemed to go on for forever, a sea of nothingness, white on white, so much like the whiteness of certain memories, white walls, and white floors, white flower vases and chairs—oh, but that was a long time ago, a whole life-time ago.

Something stirred within him, a pinprick of the heart, and he felt—rather than heard—Roxas say:

_‘Now you’re just using me as an excuse to procrastinate.’_

It was a very disheartening way to bring Sora down from his heightened state of meta-philosophical musings. 

Sora puffed his cheeks, blew an indignant breath of air out his nose, and thought,  _'Party pooper.'_

The wisp of air rustled the paper in front of him, making it skim the table a good few inches to the left, so that it was almost touching the arm of the person who sat beside him. Somewhere underneath the low coffee table, Kairi's pink-socked toes flexed once, twice, before she sighed and pushed the paper back in front of Sora's view.

"Want my help _now_?"

Sora groaned and brought his head straight down onto the piece of paper, which made a poor shield between his forehead and the solid table underneath.

"More like, do I have to _do_ this now?"

On the other side of him, he could hear the faint scratching of pencil on paper, indicating that Riku was making progress. He turned his head to the side and aimed a pout in the older boy's direction.

"Why do you have to be such a goody-goody? They said we can turn this in whenever we're ready," he grumbled half-heartedly.

Riku grinned, not once wavering in his work, "Goody-goody? _Really_? Since when has that ever applied to me?"

"Riku, I _hate_ math, can't we just take them up on their offer and wait until later to deal with this?"

He felt Kairi's hand land on his shoulder, "Sora, the school board's being really generous as it is. You guys have missed out on _a lot_ and you shouldn't take their kindness as an excuse to—"

"But it's a really _good_ excuse!" Sora abruptly sat up and then promptly flopped onto his back without missing a beat, "We're out doing the worlds a service, and we're busy! Next week we've got that Master Exam or whatever from Yen Sid—"

"Exactly Sora," Riku put his pencil down and twisted to face the other boy, a very serious but well meaning expression on his face, "We've got a week. We might as well use it to make a dent in this work load."

Sora's voice came low, a slight whine in the edges, "Oooor, we could use it to train."

This time it was Kairi who offered a rebuttal, "Yen Sid and the King gave you guys this week to _relax_. They told you specifically not to train."

Riku didn't wait for Sora to come back with another reason to procrastinate, "I don't know about you, but sitting around doing nothing sounds like an _awful_ way to relax. I might as well do something productive."

With this, he turned back around and took his pencil up again. There was a tense silence as Sora and Kairi's eyes locked, and with just a look Kairi _dared_ him to try and drag this out as painfully as possible.

Reluctantly, Sora yielded and sluggishly sat back up, "Oh fine, but you're gonna have to walk me through this."

Kairi nodded and scooted an inch closer, pushing the textbook in between them, "First things first, copy the problem down."

Sora bit his lip and snuck a glance to his right to see how Riku was handling his workload. As expected, he was breezing through the problems. A hint of jealously sprouted within Sora—math had always been a strong point of Riku's, and he had been a year ahead of his peers to begin with, so there was basically no point in catching up, really.

He scratched at the back of his neck in a defeated sort of manner, "Kairi, these are some weird problems—they've got _letters_ in them."

To his surprise, Riku let out a laugh, "Oh, this is gonna be good."

A faint blush seeped across Sora's nose, "Sh-shut up! I'm just not as good at this stuff as you guys are…"

Kairi giggled softly, not teasing but genuinely reassuring, "It's okay Sora, we'll take it one step at a time."

"R-right," Sora dug his thumbnail into the paint covering his pencil, not sounding confident at all, "Okay, so…why exactly are there letters in these problems?"

Again, to his surprise, Riku followed Kairi's lead and scooted in closer as well, so that Sora was flanked on both sides, "That's because the letters stand for an unknown number. You have to figure them out to solve the problem."

Sora crossed his arms, demonstrating his penchant for stubbornness, "Aren't you supposed to be working on your own stuff?"

Riku scoffed, but he was grinning all the same, "I'll treat helping you as a sort of review."

Kairi rolled her eyes and smiled, ever amused at how a deep-rooted rivalry was still present at even this level of their friendship.

"Take this x here," she steered the conversation back into academic territory, writing out the problem on Sora's paper, "You need to move everything but the x to one side. That'll tell you what value it has."

"Value? But it's just an x, I don't get it…"

Kairi shook her head, "No, Sora, you don't understand, these are _numbers_."

Sora made an exasperated noise and pushed the paper further down the table, letting his upper body follow suit and sprawl across the wood, "Then why don't they just _use_ numbers instead of letters?"

Riku and Kairi traded glances over Sora's head. This wasn't going so smoothly—which they had expected, because this was how it _always_ was with Sora and homework, but that didn't make it any less taxing on their patience. Kairi gave Riku a little flick of the head, motioning to let him know it was his turn to try.

Riku's tongue darted out to wet his dry lips before he took a deep breath and slid the paper out of Sora's hands and back to the edge of the table.

_'Baby steps indeed'_

Riku began writing a new problem on the sheet of paper, "Try looking at it like this, Sora."

Sora curiously sat back up and silently peered over the page. He briefly made a note of Riku's swift strokes as he constructed a completely original problem with ease, bold and straight characters in an obedient straight line, tucked nicely under the line that Kairi had made previously, curly, round and soft, but no less compliant on the eyes.

Sora sat sandwiched between his two friends, feeling slightly inadequate in comparison, silently thankful that his sorry excuse for chicken scratch had not been the first to mar the sheet of paper.

"Now," Riku began, "think of x as a mystery. It stands for a number, but for some reason or another, we don't know _what_ number it is. So x is just a placeholder until we solve the mystery."

Sora's spine straightened a little in interest, "I like mysteries."

Riku had to resist the urge to flash a prideful smile in Kairi's direction, and instead continued the lesson, "We can use anything we want really, like x, z, or even—"

"Make it a heart."

Riku blinked at Sora, then at Kairi, who just shrugged in a way that suggested he just go with it.

"Um….okay," he slowly erased his x's and replaced them with carefully crafted hearts, "So our job is to….solve for the heart."

Sora slouched again, "That's the bit I don't get."

Kairi felt like it was her turn to intervene, sliding the paper back across the table, "The heart is stuck in the middle of a mess of numbers. Using things like addition and division, we peel away at the stuff surrounding it until it's all gone, and we have just the heart."

"….and whatever we do to the heart side, we do to the other side too?"

Kairi actually clapped in her excitement, "So you _were_ paying attention earlier!"

To her and Riku's relief, Sora took up his pencil and cautiously pressed it against the paper, attempting to move the numbers around. With some gentle prodding between them, they were able to walk him through the first problem with little resistance—it only got easier from there, although Sora kept making cheesy parallels about 'digging deep to find the heart' and at one point Riku made a big show of openly mocking this by searching under the table for the script Sora was supposedly getting his lines from.

Kairi and Riku had to hesitate at some of the more farfetched analogies Sora made, wondering if it was truly okay for them to indulge him with things like, "Uh….yeah, it sort of _is_ like getting to know someone's heart…I guess" but he was happy and confident in his work for once, and he was…learning? Maybe?

He was getting the right answers, at any rate.

But then they got to the next section.

"Alright, so…now we have to deal with two hearts?" Sora asked, tentatively looking over the textbook, cautiously wary of the fact that the upcoming problems were showcasing letters other than just x.

"No, that's _i_. It's always the same number, no matter wha—"

"But you just _said_ —you just spent all this time _teaching_ me—"

"The _i_ is special Sora. It _always_ represents the imaginary number."

Riku very nearly opened his mouth to say that this wasn't true, but when Kairi shot him a glare so full of fire over the top of Sora clutching his head in his hands, he could practically _hear_ the words, "Shutupshutupshutup" jumping for her thoughts into his.

Sora, oblivious to all of this, continued to rub his poor head, "So now the numbers aren't even _real_?!"

Riku pinched the bridge of his nose with a sigh, then, in the spirit of continuing their silent conversation, threw a look back at Kairi, _'What now?'_

Slightly widened eyes, a subtle shake of the head, and a quick tug of the shoulders, _'I don't know, you try calming him down!'_

Between them, Sora let out a wail and then flung himself backward onto the floor in defeat.

Kairi and Riku blinked at each other.

Then all at once, all three of them let out a collective sigh. And he’d been doing so _well_ , too…

Kairi bit her lip, racking her brain for a way to salvage Sora’s interest, before gently nudging his shoulder, “They’re not… _really_ imaginary. It’s just…here, let me show you.”

Sora begrudgingly sat up and hugged his knees to his chest, defiant, “I bet people don’t even _use_ these numbers, I can’t think of a single reason why I’d ever have to sit down and calculate the square mass trinomial or whatever of these things.”

“That’s not—” Kairi started, before deciding to just leave it, “And anyway, imaginary numbers are actually very important. They’re used in fields like electrical engineering and particle physics. Some map makers use them, and—”

She stopped when she realized that both boys were giving her very wide-eyed stares.

She shot an exasperated look back and forth between both boys, her face clouding over in pink, “Don’t look at me like that. While you two have been traipsing the galaxies, I was actually _in_ class, studying this stuff.”

Sora buried his forehead in the little valley his knees created, “I am a teenage boy, Kairi. I am more concerned about _saving_ the world than understanding it on a molecular level.”

“ _Anyways_ ,” Riku could tell that the current task at hand was about to get derailed unless he steered it back in a productive direction, “let’s just start with what you _do_ know. You know how to square numbers, right? Two times two, three times three, that sort of thing?”

Sora gave him a look that read, _‘I’m not dumb Riku, I know how to multiply.’_

Kairi meanwhile was sulking at the other end of the table, arms crossed, muttering something about, “Chip and Dale probably use…on their gummi systems…”

Riku fought the urge to roll his eyes at the matched sour expressions of his two best friends, thinking, _‘We’ve faced down the threat of an evil organization together, but **god forbid** we get through a little bit of homework in one piece.”_

He forged ahead, “Well, you may have noticed that squaring a number always results in a positive number. That’s why when you take the square root of things, we’ve only up until now worked with positive numbers. But what if…”

“What if we take the square root of a negative number…?” Sora said, trying to be helpful.

Riku nodded, motioning Sora back to the table, “You know the square root of 4 is 2, but what do you think happens when you take the square root of negative 4?”

“….you get negative 2?”

“No Sora,” Kairi scooted back up to the join the two, “Negative two times negative two is still a positive four. You don’t get something natural when you square root a negative number—that’s the whole point of _i_.”

“It’s sort of like…another mystery,” Riku attempted to piggy-back off of the same logic that had excited Sora before, “You get something that isn’t a normal number, and regular math isn’t adequate to describe a negative square root, so _i_ is sort of like…another place holder.”

There was something working behind Sora’s eyes, gears turning and shifting, and for a moment Riku and Kairi just watch him, concerned.

“That’s…not a mystery,” he began, quietly, “That’s not even imaginary. It’s…”

He didn’t know what he was trying to say.

He turned to Kairi, “Can you count imaginary numbers?”

There was something urgent in Sora’s voice, something that made Kairi hesitate and pick her words a bit more carefully, “I don’t…think so. I mean…you can’t count imaginary apples, for example, if that’s what you mean…”

Riku countered, “Well, you can’t technically count negative apples either, but those numbers are considered real.”

“So imaginary numbers are real too?”

There was still that vague undertone, something not yet definable, but it settled in Riku and Kairi’s chests all the same, made them heavy and worried. They were just talking about math…right?

After a moment, Kairi said, “Not in the mathematical sense of ‘real’, but yeah, you can say they exist.”

“They exist,” Sora repeated, firmly, as if committing it to memory.

Riku continued, “They just don’t work like normal numbers do, they don’t…fit neatly into our number system, like everything else.”

“They mess up the math,” Sora replied, almost too quickly, like he was reciting something out of a far-off memory.

Kairi took a breath, almost said something, until she glanced at Riku and noticed something darkening in his expression, like something was starting to click, mixed with something akin to what a person who’s been made to eat their own words might look like, and found them to taste awful.

“No, it’s more—,” Riku tried to explain, not sure if even _he_ knew what he was trying to say now, “It’s more they…have their own place.”

“Why do we call them imaginary then?”

Neither of them even _dared_ to say, ‘ _They’re just numbers Sora,’_ and they didn’t even consider telling him to move on from this, that yes, Sora, they’re not really imaginary, that’s just what they’re called, no we don’t know why they decided to call them that, just drop it.

Kairi tried to be reasonable, “It was just easier that way, I suppose.”

“That’s dumb,” Sora said automatically, “That’s not fair, it’s—”

Riku and Kairi looked at each other, and suddenly they knew that this wasn’t about math, because they had seen this before.

Sora was at his core a happy kid—they knew this. He was one of the most genuine people, really _genuinely_ warm and outgoing. He was the kid who made literal friends with everyone he met, the one with an almost permanent grin plastered to his face, and a sunny disposition, not because he was trying too hard, but because that was his default setting, it was just who he _was_. His laughter was infectious because it was real.

But sometimes—only rarely, and without pattern or warning—sometimes Sora just had these moments.

Riku could remember these incidents as far back as their early childhood—Sora crying out of seemingly nowhere, not even sad for his own benefit, as if some cosmic entity had just gripped him and asked him to be sad on its behalf and he complied, because he was just that good of a person.

Kairi first remembered it the day they first played together—crouched under palm trees, her showing him her necklace, the only earthly possession she’d brought with her over the waves, and the moment he touched it he had sat down and cried.

_“Sora, what’s wrong?”_

_“I miss—”_

But he could never explain why or even who it was he supposedly missed.

Even now, they could see the droplets of water forming in his eyes, tears that weren’t fully his, a sadness in his eyes that was equal parts distant and personal.

“It’s not fair,” he said it again, “It shouldn’t…Nobody should have to—Nobody should…”

He rubbed at his eyes with the heel of his palm, “Sorry, I’m being stupid, this is stupid, sorry.”

There was a moment of just silence and small sniffles from Sora, before Kairi unceremoniously crawled over and wrapped her arms around him, guided his head to the crook of her shoulder and let him stay there without a word. Even now he couldn’t fully understand what was making him so upset, but he had an idea—just snatches of gray-moral thoughts, various bits and ends, an endless repeat of what he’d done and what was right and what was wrong, just a kid playing hero, but what kind of hero didn’t answer to his own actions? Somewhere deep down he knew what was wrong, and in a week’s time, Sora would take his test, and all of this would crystalize into a clear understanding, materialize into red hot anger at the injustice of it all.

But he didn’t know that yet.

For now, he just let Kairi hold him, felt her make some gesture in Riku’s direction before he felt strong arms enfold them both. It was warm, and it was quiet, and it was enough.

When Sora’s breathing had stopped hitching at intervals, Riku’s voice came soft, “We don’t have to do homework if you don’t want.”

Sora just wiped the back of his hand across his lids, sniffed one last time before saying, almost forcefully, “No. I’m going to learn this. I want to understand,” before gently uncocooning himself from his best friends and making his way back to the table.

Riku and Kairi followed suit, once again flanking him on either side, although they perhaps sat a little closer than before. Sora was glad for the company.

Tomorrow he would forget about this, or at the very least not actively remember, because the other two were going to conspicuously drag him out to the beach for some much needed downtime. He would not comment on the obvious ploy to get his mind off of things, because he would be so happy it wouldn’t even cross his mind—that was what these two did best, after all, making Sora happy.

And in a week or so it wouldn’t matter, this was all going to get ripped out of him again, but for now it was alright, less than okay, but more than enough, just a best friend on each side to comfort him.

And eight by eleven inches of blank possibility.


End file.
